Originally Posted by

**sfspitfire23** A point Q is chosen in the unit square. What is the density function of the sum of the coordinates? Of the product of the coordinates?

Work-

Let X be a r.v. on (0,1) and let Y be a r.v. on (0,1). These are independent.

Then, I let V = X + Y.

So, I then perform P(V < c) where c is just some constant (cumulative distribution function). I transform the inequality like so: P(Y < c - X).

I feel like I'm very close to solving this but here is where I get stuck. What do I do now?